This Internet Archive emulated item contains a 25MB Macintosh formatted disk image with an install of Mac System 7.5.3.
"System 7.5.3, a major bug-fix update that also included Open Transport
for other PowerPC-based machines as well as some 68k-based machines.
7.5.3 also made several improvements to the 68k emulator, and added
translucent dragging support to the Drag Manager. It was also the first
version of Control Strip for all Macs. This was also the first version of Mac OS to support SMP. (9500/MP)
System 7.5.3 Revision 2 included: performance enhancements; better
reliability for PowerBooks using the third-party RAM Doubler program;
improved reliability for PowerBook 500, 2300, and 5300 series computers
with the PowerPC Upgrade Card; improved reliability when using the
Startup Disk control panel; and improved reliability when copying files
to 1 GB hard disks."